Vaccaria is a monotypic genus of flowering plants in the pink family containing the single species Vaccaria hispanica. It is known by several common names including cowherb, cowcockle, cow basil, cow soapwort, and prairie carnation. Its subspecies were previously treated as separate species.[1]

It is an annual herb with blue-gray, waxy herbage and pale pink flowers.

The seeds of Vaccaria are used in Chinese medicine. This medicinal ingredient is known as Wang Bu Liu Xing. It is supposed to promote diuresis and milk secretion, activate blood circulation and relieve swelling.